1. Field of the Invention
This invention relates to adjustable ballast systems for vehicles.
2. Background of the Invention
Vehicles adapted for carrying loads such as pick-up trucks and vans may have difficulties when travelling unloaded in the winter because of the lack of weight over the rear wheels. These vehicles, for example, are usually engineered for optimum handling with a load in the rear over the drive wheels. Traction and handling problems may arise when the vehicle is traveling without a load over the drive wheels, particularly in snowy or icy conditions. Many owners try to offset this by placing heavy objects in the load area such as sandbags. However, this tends to be very inconvenient because the items take up space needed for cargo or passengers may cause dangerous shifts in weight by moving around and may be tiring and difficult to handle for women and individuals with some disability.
Shortcomings of the Existing Art
None of the existing prior art discloses or describes to a hollow removable bedliner for a vehicle to which ballast may be added or removed, uses a liquid, and which include baffles and a vent.
One set of devices in the prior art utilizes closed containers filled with various materials and placed inside the bed of the vehicle. However, these devices are usually large and bulky and difficult for some drivers to handle. Furthermore, many of these devices require a separate bedliner to increase friction on top of these devices. Furthermore, once the truck is loaded and the additional ballast is no longer needed, the devices must be somehow un-weighted to avoid limiting the vehicle can carry. Mayer in U.S. Pat. No. 6,079,741, Malinowski, et al. in U.S. Pat No. 6,027,139 and Hartenburg in U.S. Pat. No. 5,494, 395 are illustrative of these devices.
Another example Ryan et al. in U.S. Pat. 7,624,273 disclose a large mat for placing in the rear of a pickup truck. The mat has cross-members integrally attached to the mat to furnish the needed weight. When not needed the mat is to be rolled up and stored, presumably in the bed of the truck. There are several disadvantages to this system. First it would be very difficult to get sufficient weight in such an arrangement. On the other hand even a limited weight would be difficult for many individuals to handle. The mat once rolled up would take up needed space and the top of the mat would create problems in the bed. Mayer U.S. Pat. No. 6,079,741 discloses a pair of ballast tanks for containing sand to be placed in the rear of a pick-up truck. This device presents similar difficulties. The tanks would be heavy and difficult to handle even when empty. They would be difficult to empty and would occupy substantial space needed for cargo. A significant supply of sand is frequently not available and filling may be difficulty in freezing conditions. Additional devices are limited to solid ballast such as sand include Ryan et al. 273, Malinowski, et al. 139, Anderson U.S. Pat. No. 5,330,227, Chamberlain, U.S. Pat. No. 5,172,953 and Tackett, U.S. Pat. No. 5,657,916.
Several devices utilize a semi-permanent bed-liner located inside the rear part of the truck and providing space for ballast between the liner and the truck body. These devices are difficult to remove, generally requiring several individuals, reduce the load capacity and essentially require that the additional ballast be carried throughout the winter season. They generally use solid ballast with the accompanying disadvantages described above. In addition to those listed above, these semi-permanent liners include Chamberlain, U.S. Pat. No. 5,172,953, Smith, U.S. Pat. No. 4,396,914.
Of the prior art Patents that potentially use liquid ballast, none provide internal baffles to reduce the internal movement of the liquid to prevent potentially dangerous “sloshing” effects when suddenly stopping or negotiating sharp curves, or to provide internal structural support to the ballast system.